Signal channel address system

ABSTRACT

An electronic selecting system for a television receiver includes a charging capacitor and a plurality of switches each coupled to one of a plurality of indicating and tuning means including a neon lamp. The charging capacitor effects application of a firing potential to a neon lamp of a selected channel and a potential less than the maintaining potential to the remaining signal channels.

United States Patent [1 1 [111 3,859,610 Rhee Jan. 7, 1975 [54] SIGNAL CHANNEL ADDRESS SYSTEM 3,746,886 7/1973 Konopka 333/15 [75] Inventor: Dong W00 Rhee, Williamsville, NY. P E Alf d E S h rzmary xaminer re mit [73] Assrgnee: GTE Sylvama Incorporated, Assistant w punter Stamford Conn- Attorney, Agent, or FirmNorman J. OMalley; 22 Filed; 7 Thomas H. Buffton; Cyril A. Krenzer [21] Appl. No.: 445,796

[57] ABSTRACT {52] Cl 334/ 307/264 325/468 An electronic selecting system for a television receiver 51 Int. Cl H03j 5/22 rioak 1/14 includes a charging Capacitor and a plurality 0f [58] Field of Search 334/l5 367/264 switches each coupled to one of a plurality of indicat- 3 ing and tuning means including a neon lamp. The

charging capacitor effects application of a firing po- [56] References Cited tential to a neon lamp of a selected channel and a potential less than the maintaining potential to the re- UNITED STATES PATENTS mamm s1 nal channels. 3,503,018 3/1970 Cavanagh 334/15 g g 3,528,044 9/1970 Manicki 307/320 8 Claims, 1 Drawing Figure POWER SOURCE POWER SOURCE VARACTOR TUNER VOLTAGE POWER SOURCE POWER SOURCE VARACTOR TUNER 'f VOLTAGE CROSS REFERENCE TO OTHER APPLICATIONS A pending U.S. application entitled Varactor Tuner Band Switch Circuitry, filed in the name of Paul Eshelman LeFevre, bearing Ser. No. 326,758, now U.S. Pat. No. 3,790,909, and assigned to the assignee of the present application suggests a mechanical system of signal channel address.

BACKGROUND OF THE INVENTION The prior art suggests a channel address system wherein a touch contact or mechanical type switch is employed to cause activation of a transistor. The current flow through this activated transistor develops a potential which is employed to inhibit conduction of other signal channels through a rather elaborate negative feed-back system. Moreover, a latching system including a plurality of transistors is employed to maintain conduction in the selected channel even though the switch is no longer operational. Thus, potentials are provided for an indicating lamp as well as for an adjustable resistor for varactor tuning.

In another known technique a pair of mechanical switches are utilized in each signal channel to effect selected application of potentials to a neon lamp in one circuit and to an alterable resistor in another circuit. Thus, the neon lamp provides channel indication while the alterable resistor provided varactor tuning potentials. Moreover, all of the switches are mechanically interconnected by a so-called slack-wire" system wherein activation of any one pair of switches caused de-activation of the remaining switches.

Although the above-mentioned channel address systems have been and still do receive favorable comment in certain applications, it has been found that each leaves something to be desired in other applications, such as present-day television receivers. For example, touch contact or mechanical switching systems employing numerous transistors and latching systems are relatively expensive and susceptible to catastrophic failure due to the relatively large component count. Moreover, multiple mechanical switches and slackwire" techniques have been found undesirably difficult to maintain and lacking in the necessary reliability for repetitive use.

OBJECTS AND SUMMARY OF THE INVENTION An object of the present invention is to provide an enhanced electronic signal channel address system for a television receiver employing a varactor tuner. Another object of the invention is to provide a signal channel address system having improved reliability. Still another object of the invention is to provide an improved signal channel address system employing a desirable small number of inexpensive and readily obtainable components.

These, and other objects, advantages and capabilities are achieved in one aspect of the invention by a signal channel address system having a charge capacitor, a plurality of parallel coupled channel indicating and tuning means each including a neon lamp and a alterable resistor coupled to a varactor tuner, and a switch for effecting application of a firing potential to the neon lamp of the selected channel with a potential less than the maintaining potential of a neon lamp applied to the remaining signal channels.

BRIEF DESCRIPTION OF THE DRAWING The sole FIGURE is a preferred embodiment of an electronic signal channel address system suitable for use in a television receiver employing a varactor tuner.

PREFERRED EMBODIMENT OF THE INVENTION For a better understanding of the present invention together with other and further objects, advantages and capabilities thereof, reference is made to the following disclosure in conjunction with the accompanying drawmg.

In the drawing, a preferred form of a signal channel address system includes a first potential source 5 having first and second impedances, 7 and 9 respectively, coupled thereto and to a charge storage means in the form of a capacitor 11. A plurality of channel indicating and tuning means l3, l5, and 17 are parallel coupled to the junction of the charge storage means 11 and the second impedance 9. A plurality of switches 19, 21 and 23 are each coupled to the junction of the first impedance 7 and charge storage means 11 and selectively connected to one of the channel indicating and tuning means 13, 15, and 17.

Since each one of the channel indicating and tuning means 13, 15, and 17 is identical, a description of one appears appropriate. The channel indicating and tuning means 13 includes a diode 25, neon lamp 27, and first and second resistors 29 and 31 series connected intermediate the junction of the second impedance 9 and charge storage means 11 and a potential reference level or circuit ground. The junction of the series connected resistors 29 and 31 is connected to the base of a transistor 33 having an emitter connected to circuit ground and a collector connected to one end of an alterable resistor 35. The other end of the alterable resistor 35 is connected to a second potential source 37 and by way of a resistor 41 to a varactor tuner of a television receiver. Also, the adjustable arm 43 of the alterable resistor 35 is coupled by a diode 45 to the varactor tuner. v As to operation, applying power to the signal receiver causes activation of a random one of the plurality of signal channels depending upon which neon lamp has the lowest firing voltage requirement. Moreover, activation of one neon lamp causes an immediate reduction in potential applied to the remaining neon lamps Since the maintaining potential of a conducting neon lamp is lower than the firing potential. Thus, the remaining un-activated signal channels remain unactivated until another channel selection is made.

Alternatively, the signal receiver may be designed in a manner such that a specific channel indication rather than a random channel indication is provided when the signal receiver is activated. In this embodiment, a particular signal channel is associated with the receiver off-button. Activating the off-button de-energizes the receiver except for the selected signal channel indicating and tuning circuit which remains energized. Thus, activation of the receiver by a viewer is effected by a particular signal channel selection whereupon the selected channel is activated and all remaining channels, including the off-button" channel, inactivated as will be explained hereinafter.

More specifically, assume channel indicating and tuning means 13 is turned on or conducting due to the potential applied thereto via the first power source 5 and second impedance 9. Current flows through the diode 25, neon lamp 27, and first and second resistors, 29 and 31. Thereupon, the transistor 33 will saturate or conduct at a saturation level whereupon the collector of the transistor 33 and one side of the alterable resistor 35 will be at an approximate ground level potential. The alterable resistor 35 will have a potential thereacross in accordance with the second potential source 37 coupled therethrough to circuit ground. Thus, the potential, as determined by the adjustable arm 43 of the alterable transistor 35, will be applied to the varactor tuner to effect a tuning potential for the particular selected signal channel. Moreover, other potentials available at the alterable resistors 43' and 43" of the other channel indicating and tuning means 15 and 17 cannot appear at the diode 45 due to the reverse bias condition of the diodes 45' and 45" of the other channel indicating and tuning means 15 and 17.

When a channel change is desired, such as the energization of the channel indicating and tuning means 17 for example, the switch 23 is momentarily depressed to effect closing of the contacts. Thereupon, a voltage in an amount sufficient to effect firing or conduction of the neon lamp 27" will be applied from the first potential source 5 via the first impedance 7 and switch 23.

Prior to activation of the switch 23, the charge storage neans or capacitor 11 has a potential thereon due to the difference between the first potential source 5 and the maintaining voltages of the neon lamp 27 of the channel indicating and tuning means 13. For example, the maintaining voltage of the neon lamp 27 would be about 80-volts while the first potential source 5 would be about l20-volts. Thus, a potential differential or charge of about 40-volts would appear at the capacitor 11 prior to activation of the switch 23.

However, activating the switch 23 causes application of a firing potential (about 120-volts) to the neon lamp 27" of the channel indicating and tuning means 17. Thereupon, the neon lamp 27" will conduct or fire and the potential across the noen lamp 27" will drop to the maintaining voltage (about 80-volts). This negativegoing potential excursion, firing to maintaining potentials or about 120 to 80, available at the junction of the first impedance 7 and capacitor 11 will be transferred by the capacitor 11 to the junction of the capacitor l1 and second impedance 9.

Since the channel indicating and tuning means 13 has a maintaining potential (about 80") thereon prior to activation of the switch 23, the above-mentioned negative-going potential excursion (about 40") will momentarily reduce the maintaining potential (about 80") by the potential excursion (about 40). Thus, the potentials applied to the neon lamps 27 and 27 of the channel indicating and tuning means 13 and 15 will be well below the firing potential or maintaining potentials of the neon lamps 27 and 27 whereupon conduction therethrough will be negated. As a result, the potential appearing at the alterable arm 43" of the adjustable resistor 35" will be applied to a varactor tuner to effect a selected desired tuning.

Thus, there has been provided a unique electronic signal channel address system for a signal receiver. The system is inexpensive of components and construction while providing reliable channel selection, indication, and tuning. Moreover, the positive triggering action for channel selection and inactivation of a prior employed channel is unavailable in any known address system.

While there has been shown and described what is at present considered the preferred embodiment of the invention, it will be obvious to those skilled in the art that various changes and modification may be made therein without departing from the invention as defined by the appended claims.

What is claimed is:

1. In a signal receiver having first and second potential sources and a varactor tuner, a signal channel address system comprising:

charge storage means coupled by first and second impedances to said first potential source;

a plurality of parallel coupled channel indicating and tuning means each coupled to said charge storage means and second impedance and to said second potential source and varactor tuner; and

a plurality of switching means each coupled to said charge storage means and first impedance and to one of said plurality of parallel coupled channel indicating and tuning means whereby activation of one of said switching means causes energization of a selected one of said parallel coupled channel indicating and tuning means and de-energization of the remainder of said parallel coupled channel indicating and tuning means.

2. The signal channel address system of claim 1 wherein each one of said plurality of parallel coupled channel indicating and tuning means includes a series connected diode and neon lamp with a junction therebetween coupled to one of said plurality of switching means.

3. The signal channel address system of claim 1 wherein each one of said plurality of parallel coupled channel indicating and tuning means includes a series connected diode, neon lamp, and pair of resistor coupling said charge storage means and second impedance to a potential reference level and a transistor having a base connected to the junction of said resistors, an emitter connected to circuit ground, and a collector connected to an alterable resistor coupled to the second potential source and via a diode to said varactor tuner.

4. A signal channel address system for signal receivers employing a varactor tuner comprising:

first and second potential sources;

a series connected charge storage means and first impedance shunted by a second impedance and coupled to said first potential source;

a plurality of parallel coupled channel indicating and tuning means each coupled to said charge storage means and second impedance and to said second potential source and said varactor tuner; and

a plurality of switching means coupled to said charge storage means and first impedance with each one of said switching means connected to one of said plurality of parallel coupled channel indicating and tuning means whereby activation of one of said switching means causes application of a potential from said first potential source to a selected channel indicating and tuning means in an amount sufficient to effect conduction thereof and a reduction in potential applied to the remaining channel indicating and tuning means in an amount sufficient to to effect non-conduction thereof.

5. The signal channel address system of claim 1 wherein each of said plurality of parallel connected channel indicating and tuning means includes a diode,

7. The signal channel address system of claim 1 wherein each one of said parallel coupled channel indicating and tuning means includes a series connected neon lamp and diode and a switching means couples the junction of said neon lamp and diode to the junction of said charge storage means and first impedance.

8. The signal channel address system of claim I wherein each one of said channel indicating and tuning means includes a neon lamp for indicating channel selection and an alterable resistor coupled to said varactor tuner for signal channel tuning.

P0405) I UNITED STATES PATENT OFFICE 5 9 CERTIFICATE OF CORRECTION mam. 3,859,610- Dated January 7,1975

Dong Woo Rhee 7 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 4, Line 66: "claim 1" should read claim 4 Co l. 5, Line 4 "claim 1" should read claim 4 Col. 6, Line 1 "'c1aim 1" should read claim 4 Col. 6, Line 7 I: "cleim 1" should read claim 4 Signedsnd sealed this'4th day of March 1975.

(SEAL) Attest:

C. MARSHALL DANN RUTH C. MASON Commissioner of Patents Arresting Officer and Trademarks 

1. In a signal receiver having first and second potential sources and a varactor tuner, a signal channel address system comprising: charge storage means coupled by first and second impedances to said first potential source; a plurality of parallel coupled channel indicating and tuning means each coupled to said charge storage means and second impedance and to said second potential source and varactor tuner; and a plurality of switching means each coupled to said charge storage means and first impedance and to one of said plurality of parallel coupled channel indicating and tuning means whereby activation of one of said switching means causes energization of a selected one of said parallel coupled channel indicating and tuning means and de-energization of the remainder of said parallel coupled channel indicating and tuning means.
 2. The signal channel address system of claim 1 wherein each one of said plurality of parallel coupled channel indicating and tuning means includes a series connected diode and neon lamp with a junction therebetween coupled to one of said plurality of switching means.
 3. The signal channel address system of claim 1 wherein each one of said plurality of parallel coupled channel indicating and tuning means includes a series connected diode, neon lamp, and pair of resistor coupling said charge storage means and second impedance to a potential reference level and a transistor having a base connected to the junction of said resistors, an emitter connected to circuit ground, and a collector connected to an alterable resistor coupled to the second potential source and via a diode to said varactor tuner.
 4. A signal channel address system for signal receivers employing a varactor tuner comprising: first and second potential sources; a series connected charge storage means and first impedance shunted by a second impedance and coupled to said first potential source; a plurality of parallel coupled channel indicating and tuning means each coupled to said charge storage means and second impedance and to said second potential source and said varactor tuner; and a plurality of switching means coupled to said charge storage means and first impedance with each one of said switching means connected to one of said plurality of parallel coupled channel indicating and tuning means whereby activation of one of said switching means causes application of a potential from said first potential source to a selected channel indicating and tuning means in an amount sufficient to effect conduction thereof and a reduction in potential applied to the remaining channel indicating and tuning means in an amount sufficient to to effect non-conduction thereof.
 5. The signal channel address system of claim 1 wherein each of said plurality of parallel connected channel indicating and tuning means includes a diode, neon lamp, and first and second resistor series connecting said second impedance and charge storage means to a potential reference level.
 6. The signal channel address system of claim 1 wherein an impedance couples said second potential source to said varactor tuner and each one of said plurality of parallel connected channel indicating and tuning means includes a transistor and alterable resistor series coupling said second potential source to a potential reference level and said alterable resistor includes an adjustable arm coupled by a diode to said varactor tuner.
 7. The signal channel address system of claim 1 wherein each one of said parallel coupled channel indicating and tuning means includes a series connected neon lamp and diode and a switching means couples the junction of said neon lamp and diode to the junction of said charge storage means and first impedance.
 8. The signal channel address system of claim 1 wherein each one of said channel indicating and tuning means includes a neon lamp for indicating channel selection and an alterable resistor coupled to said varactor tuner for signal channel tuning. 